CN111614892A

CN111614892A - Face image acquisition method, shooting device and computer-readable storage medium

Info

Publication number: CN111614892A
Application number: CN202010348778.7A
Authority: CN
Inventors: 李修新; 范铁道
Original assignee: Shenzhen Infinova Intelligent Technology Co Ltd
Current assignee: Shenzhen Infinova Intelligent Technology Co Ltd
Priority date: 2020-04-28
Filing date: 2020-04-28
Publication date: 2020-09-01
Anticipated expiration: 2040-04-28
Also published as: CN111614892B

Abstract

The application is applicable to the technical field of face recognition and provides a face image acquisition method, a shooting device and a storage medium, wherein the face image acquisition method comprises the following steps: acquiring brightness information of a first image currently displayed on a shooting interface in a shooting mode; determining the type of a target scene of a shooting scene where the face is located at present according to the brightness information; if the type of the target scene is a backlight scene, determining that a target shooting mode of the shooting device is a backlight shooting mode, and determining that a target working state of an infrared lamp arranged on the shooting device is an opening state; and adjusting the shooting mode to be a backlight shooting mode and adjusting the current working state of the infrared lamp to be an opening state, and then shooting to obtain a target face image. According to the human face image acquisition method, the brightness of the human face is improved by starting the infrared lamp in the backlight shooting mode, so that the background information of the image is not lost while the brightness of the human face part in the target human face image is improved, and the overall quality of the image is improved.

Description

Face image acquisition method, shooting device and computer-readable storage medium

Technical Field

The present application belongs to the field of face recognition technology, and in particular, relates to a face image acquisition method, a photographing device, and a computer-readable storage medium.

Background

The face recognition technology is a biometric technology for identity recognition based on face feature information of a person, and is widely applied to various access control or monitoring systems at present. When the face is in a backlight scene, the face in the acquired face image is usually dark or even completely black, which increases the difficulty of subsequent face recognition. The traditional solution is to brighten the human face forcibly by the backlight compensation exposure function, however, the backlight compensation can cause the background in the human face image to be overexposed seriously, thereby causing the background information of the image to be lost and reducing the overall quality of the image.

Disclosure of Invention

The embodiment of the application provides a face image acquisition method, a shooting device and a computer readable storage medium, which can solve the problems that the background information of an image is lost and the overall quality of the image is low due to the fact that the image background is seriously exposed under the condition that the face of a person in a face image is dark by a traditional backlight compensation method.

In a first aspect, an embodiment of the present application provides a face image acquisition method, which is applied to a shooting device, an infrared lamp for emitting infrared light is arranged on the shooting device, and the face image acquisition method includes:

acquiring brightness information of a first image currently displayed on a shooting interface in a shooting mode; the first image comprises a human face;

determining the type of a target scene of a shooting scene where the face is located at present according to the brightness information;

if the target scene type is a backlight scene, determining that a target shooting mode of the shooting device is a backlight shooting mode, and determining that a target working state of the infrared lamp is an opening state;

and adjusting the shooting mode to be the backlight shooting mode, adjusting the current working state of the infrared lamp to be the starting state, and then shooting to obtain a target face image.

Further, the brightness information is used for describing the brightness value of each pixel contained in the first image; correspondingly, the determining the target scene type of the shooting scene where the face is currently located according to the brightness information includes:

determining a brightness average value of the first image according to brightness values of all the pixels contained in the first image;

determining a brightness variance of the first image according to the brightness average value;

determining an exposure effect value of the first image according to the brightness average value, a preset shutter speed of the shooting device and a preset exposure gain of the shooting device;

determining a brightness average value of the face region according to brightness values of pixels contained in the face region in the first image;

and determining the type of the target scene according to the brightness variance, the preset exposure gain, the exposure effect value and the brightness average value of the face region.

Further, the determining the target scene type according to the brightness variance, the preset exposure gain, the exposure effect value, and the brightness average value of the face region includes:

if the exposure effect value is greater than or equal to a first preset exposure effect value threshold value and the brightness variance is greater than or equal to a first preset brightness variance threshold value, determining that the target scene type is a backlight scene;

or, if the exposure effect value is greater than or equal to a second preset exposure effect value threshold and the brightness variance is greater than or equal to a second preset brightness variance threshold, determining that the target scene type is the backlight scene; the second preset brightness variance threshold is smaller than the first preset brightness variance threshold, and the second preset exposure effect value threshold is larger than the first preset exposure effect value threshold;

or if the exposure effect value is greater than or equal to a third preset exposure effect value threshold, determining that the target scene type is the backlight scene; and the third preset exposure effect value threshold is greater than the second preset exposure effect value threshold.

if the exposure effect value is smaller than a first preset exposure threshold, the brightness variance is smaller than a first preset brightness variance threshold, the preset exposure gain is smaller than or equal to a first preset exposure gain threshold, and the brightness average value of the face area is smaller than or equal to a first preset face brightness average value threshold, determining that the target scene type is a first preset non-backlight scene;

or, if the exposure effect value is smaller than a second preset exposure threshold, the brightness variance is smaller than a second preset brightness variance threshold, the preset exposure gain is smaller than or equal to the first preset exposure gain threshold, and the brightness average value of the face region is smaller than or equal to the first preset face brightness average value threshold, determining that the target scene type is the first preset non-backlight scene;

or, if the exposure effect value is smaller than a third preset exposure threshold, the preset exposure gain is smaller than or equal to the first preset exposure gain threshold, and the brightness average value of the face region is smaller than or equal to the first preset face brightness average value threshold, determining that the target scene type is the first preset non-backlight scene.

Further, after the determining the target scene type of the shooting scene where the face is currently located according to the brightness information, before the shooting is performed after the shooting mode is adjusted to the backlight shooting mode and the current working state of the infrared lamp is adjusted to the on state, the method further includes:

if the target scene type is a first preset non-backlight scene, determining that the target shooting mode is a backlight shooting mode, and determining that the target working state of the infrared lamp is an opening state; the first preset non-backlight scene is used for describing a shooting scene with a face not being backlight and a dark brightness of the face.

Further, after the determining the target scene type of the shooting scene where the face is currently located according to the brightness information, the method further includes:

if the type of the target scene is a weak light scene or a common illumination scene, determining that the target shooting mode is a common shooting mode, and determining that the target working state of the infrared lamp is a closed state;

and adjusting the shooting mode to be the common shooting mode, adjusting the current working state of the infrared lamp to be the off state, and then shooting to obtain the target face image.

Further, after determining that the target shooting mode of the shooting device is the backlight shooting mode and determining that the target working state of the infrared lamp is the on state, before shooting, the method further includes:

determining the target lamp light intensity of the infrared lamp based on the average brightness value of the face region;

and adjusting the current lamplight intensity of the infrared lamp to the target lamp light intensity.

In a second aspect, an embodiment of the present application provides a shooting device, an infrared lamp for emitting infrared light to a shooting object is disposed on the shooting device, and the shooting device includes:

the device comprises an acquisition unit, a display unit and a control unit, wherein the acquisition unit is used for acquiring the brightness information of a first image currently displayed on a shooting interface in a shooting mode; the first image comprises a human face;

the first determining unit is used for determining the target scene type of the shooting scene where the face is located at present according to the brightness information;

a second determining unit, configured to determine that a target shooting mode of the shooting device is a backlight shooting mode and determine that a target working state of the infrared lamp is an on state if the target scene type is a backlight scene;

and the first adjusting unit is used for adjusting the shooting mode to the backlight shooting mode and adjusting the current working state of the infrared lamp to the starting state, and then shooting is carried out to obtain a target face image.

In a third aspect, an embodiment of the present application provides a shooting apparatus, including:

a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the computer program, implements the steps of the facial image acquisition method according to any one of the first aspect.

In a fourth aspect, the present application provides a computer-readable storage medium, which stores a computer program, and when the computer program is executed by a processor, the computer program implements the steps of the facial image acquisition method according to any one of the above first aspects.

In a fifth aspect, an embodiment of the present application provides a computer program product, which, when running on a terminal device, causes the terminal device to execute the facial image acquisition method according to any one of the above first aspects.

It is understood that the beneficial effects of the second aspect to the fifth aspect can be referred to the related description of the first aspect, and are not described herein again.

Compared with the prior art, the embodiment of the application has the advantages that:

according to the face image acquisition method, under a shooting mode, luminance information of a first image is acquired; determining the type of a target scene of a shooting scene where the face is located at present according to the brightness information; if the type of the target scene is a backlight scene, determining that a target shooting mode of the shooting device is a backlight shooting mode, and determining that a target working state of an infrared lamp arranged on the shooting device is an opening state; and adjusting the shooting mode to be a backlight shooting mode and adjusting the current working state of the infrared lamp to be an opening state, and then shooting to obtain a target face image. Because when the shooting object is irradiated by the infrared lamp, the brightness of the shooting object can be improved, and meanwhile, natural light in the shooting scene cannot be influenced, so that when the human face to be shot is determined to be in the backlight scene, the brightness of the human face is improved by opening the infrared lamp on the shooting device while the backlight shooting mode corresponding to the backlight scene is adopted, the brightness of the human face is improved, the background information of the image cannot be lost while the brightness of the human face part in the target human face image is improved, and the overall quality of the target human face image is improved.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.

Fig. 1 is a flowchart illustrating an implementation of a face image acquisition method according to an embodiment of the present application;

fig. 2 is a flowchart of a specific implementation of S102 in a method for acquiring a face image according to an embodiment of the present application;

fig. 3 is a flowchart of a specific implementation of S1025 in the method for acquiring a face image according to the embodiment of the present application;

fig. 4 is a flowchart illustrating an implementation of a face image acquisition method according to another embodiment of the present application;

fig. 5 is a flowchart illustrating an implementation of a face image acquisition method according to another embodiment of the present application;

fig. 6 is a flowchart illustrating an implementation of a face image acquisition method according to another embodiment of the present application;

fig. 7 is a schematic structural diagram of a shooting device according to an embodiment of the present application;

fig. 8 is a schematic structural diagram of a camera according to another embodiment of the present application.

Detailed Description

In the following description, for purposes of explanation and not limitation, specific details are set forth, such as particular system structures, techniques, etc. in order to provide a thorough understanding of the embodiments of the present application. It will be apparent, however, to one skilled in the art that the present application may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present application with unnecessary detail.

It will be understood that the terms "comprises" and/or "comprising," when used in this specification and the appended claims, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

It should also be understood that the term "and/or" as used in this specification and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

As used in this specification and the appended claims, the term "if" may be interpreted contextually as "when", "upon" or "in response to" determining "or" in response to detecting ". Similarly, the phrase "if it is determined" or "if a [ described condition or event ] is detected" may be interpreted contextually to mean "upon determining" or "in response to determining" or "upon detecting [ described condition or event ]" or "in response to detecting [ described condition or event ]".

Furthermore, in the description of the present application and the appended claims, the terms "first," "second," "third," and the like are used for distinguishing between descriptions and not necessarily for describing or implying relative importance.

Reference throughout this specification to "one embodiment" or "some embodiments," or the like, means that a particular feature, structure, or characteristic described in connection with the embodiment is included in one or more embodiments of the present application. Thus, appearances of the phrases "in one embodiment," "in some embodiments," "in other embodiments," or the like, in various places throughout this specification are not necessarily all referring to the same embodiment, but rather "one or more but not all embodiments" unless specifically stated otherwise. The terms "comprising," "including," "having," and variations thereof mean "including, but not limited to," unless expressly specified otherwise.

Referring to fig. 1, fig. 1 is a flowchart illustrating an implementation of a method for acquiring a face image according to an embodiment of the present disclosure, in which an executing main body of the method for acquiring a face image is a shooting device, and an infrared lamp for emitting infrared light to a shooting object is disposed on the shooting device. In practical applications, the photographing device may include, but is not limited to, various electronic devices with monitoring functions, such as a security monitoring camera. In the embodiment of the application, the shooting object can be any face entering the shooting range of the shooting device.

A face image acquisition method as shown in fig. 1 may include the following steps:

in S101, acquiring brightness information of a first image currently displayed on a shooting interface in a shooting mode; the first image comprises a human face.

In practical application, when a face image needs to be collected, the shooting device can be started, so that the shooting device is in a shooting mode. The shooting device acquires brightness information of a first image currently displayed on a shooting interface in a shooting mode. The current time refers to the moment when the shooting device is in a shooting mode and a shooting object enters a shooting range of the shooting device; the luminance information of the first image is used to describe the luminance values of the respective pixels included in the first image. Wherein, the first image comprises a human face.

In the embodiment of the present application, the shooting mode of the shooting device may include, but is not limited to: a normal photographing mode and a backlight photographing mode. The photographing scenes to which the normal photographing mode is applied may include, but are not limited to, a normal lighting scene and a low-light scene, and the photographing scenes to which the backlight photographing mode is applied may include, but is not limited to, a backlight scene and a first preset non-backlight scene. The common illumination scene is used for describing a shooting scene that a shooting object is not backlit and the brightness of the shooting object is not dark; the weak light scene is used for describing a shooting scene with a shooting object not being backlit and weak illumination intensity of natural light; the backlight scene is used for describing a shooting scene of the backlight of a shooting object; the first preset non-backlight scene is used for describing a shooting scene that a shooting object is not backlight and the brightness of the shooting object is dark.

It should be noted that whether the brightness of the photographic subject is dark or not may be determined according to a magnitude relationship between the average brightness value of the photographic subject and a preset brightness threshold. Specifically, if the average brightness value of the photographic subject is greater than or equal to a preset brightness threshold value, determining that the brightness of the photographic subject is not dark; and if the average brightness value of the shot object is smaller than the preset brightness threshold value, determining that the brightness of the shot object is dark. The preset brightness threshold may be according to practical needs, and is not limited herein, and for example, the preset brightness threshold may be 90. The average brightness value of the photographic subject may be determined according to the brightness value of the pixels included in the region where the photographic subject is located in the first image. For example, the average value of the luminance values of all pixels included in the region where the photographic subject is located in the first image may be determined as the average luminance value of the photographic subject.

In the embodiment of the application, different shooting modes can correspond to different working states of the infrared lamp. The operating state of the infrared lamp may include, but is not limited to: an on state and an off state. The on state refers to a state in which the infrared lamp emits infrared light to the photographic subject, and the off state refers to a state in which the infrared lamp does not emit infrared light to the photographic subject. The first image in the backlight shooting mode is dark overall, so that a clear face cannot be obtained, and the first image in the ordinary shooting mode is bright overall, so that the clear face can be obtained. The shooting device can store the preset corresponding relation between the shooting mode and the working state of the infrared lamp in an associated mode.

In the embodiment of the application, no matter which shooting mode the shooting device is in, the brightness information of the first image can be acquired.

In an embodiment of the present application, the photographing device may determine the brightness information of the first image according to the gray scale of each pixel included in the first image. Specifically, the photographing device may determine a gray scale of each pixel included in the first image as a brightness value of each pixel, respectively. In practical applications, since each pixel in the image is usually represented by a binary number with a preset number of bits, the decimal number corresponding to the binary number with the preset number of bits used for representing each pixel can be determined as the gray scale of the pixel. The preset number of bits is the number of gray scale levels of the image. In practical applications, the predetermined number of bits is usually 8. For example, if a certain pixel included in the first image is represented by a binary number having a value of 00000000, the gray scale of the certain pixel is 0; if a pixel included in the first image is represented by a binary number having a value of 11111111, the gray scale level of the pixel is 255.

In S102, a target scene type of a shooting scene where the face is currently located is determined according to the brightness information.

In the embodiment of the application, the shooting scene where the face is currently located refers to the shooting scene where the face is located when the shooting device detects that the face exists in the first image.

As an embodiment of the present application, S102 can be specifically implemented by S1021 to S1025 as shown in fig. 2, and is described in detail as follows:

in S1021, a luminance average value of the first image is determined according to luminance values of all the pixels included in the first image.

In this embodiment, after acquiring luminance information of a first image including a human face, a shooting device determines a luminance average value of the first image according to luminance values of all pixels included in the first image. Wherein the brightness average is used to describe the overall brightness of the first image.

In a specific embodiment, the camera may determine the average value of the brightness of the first image according to the following formula:

where E represents the average luminance value of the first image, M represents the maximum value of the gray scale, hist (i) represents the number of pixels having a gray scale i included in the first image, and hist _ sum represents the total number of pixels included in the first image. For example, if the range of the grayscale is [0, 255], M is 255.

In S1022, the luminance variance of the first image is determined from the luminance average value.

In this embodiment, the photographing apparatus determines the luminance average value of the first image, and then determines the luminance variance of the first image based on the luminance average value of the first image. Wherein the brightness variance is used to describe a difference size between the brightness value of each pixel in the first image and the brightness average value of the first image.

In a particular embodiment, the camera may determine the variance in brightness of the first image according to the following equation:

wherein σ²Representing the luminance variance of the first image and abs () representing an absolute value operation.

In S1023, an exposure effect value of the first image is determined according to the brightness average value, a preset shutter speed of the photographing device, and a preset exposure gain of the photographing device.

In this embodiment, after determining the luminance variance of the first image, the shooting device determines the exposure effect value of the first image according to the luminance average value of the first image, the preset shutter speed of the shooting device, and the preset exposure gain of the shooting device. The exposure effect value is used for representing a theoretical brightness value of the first image when the shutter speed of the shooting device is a standard shutter speed and the exposure gain of the shooting device is a standard exposure gain. The standard shutter speed and the standard exposure gain of the shooting device are related to the shooting device, and the standard shutter speed and the standard exposure gain corresponding to different shooting devices can be the same or different. Illustratively, the standard shutter speed of the camera may be 1/25, and the standard exposure gain may be 1 exposure gain.

In one embodiment, the camera may determine the exposure effect value of the first image according to the following formula:

exp_value＝(E/(shutter*gain))/25；

where exp _ value represents an exposure effect value of the first image, shutter represents a preset shutter speed of the photographing apparatus, and gain represents a preset exposure gain of the photographing apparatus.

In S1024, an average brightness value of the face region is determined according to brightness values of pixels included in the face region in the first image.

In this embodiment, after determining the exposure effect value of the first image, the shooting device determines the average brightness value of the face region according to the brightness values of the pixels included in the face region in the first image.

As an embodiment of the present application, the shooting device may determine an average brightness value of the face region according to brightness values of all pixels included in the face region in the first image. Specifically, the photographing device may determine the average value of the brightness of the face region from the average value of the brightness values of all pixels included in the face region in the first image.

As another embodiment of the present application, the photographing device may further determine an average brightness value of the face region according to brightness values of pixels included in a preset key region in the face region in the first image. Specifically, the photographing device may determine an average value of luminance values of all pixels included in a preset key area in the face area as an average value of luminance values of the face area. The preset key area can be set according to actual needs, and for example, the preset key area can be an area surrounded by eyes, a nose and a mouth of a human face.

In S1025, the target scene type is determined according to the brightness variance, the preset exposure gain, the exposure effect value, and the brightness average value of the face region.

In this embodiment, the photographing apparatus may compare the exposure effect value of the first image with a first preset exposure effect threshold, compare the exposure effect value of the first image with a second preset exposure effect threshold, compare the exposure effect value of the first image with a third preset exposure effect threshold, compare the brightness variance of the first image with a first preset brightness variance threshold, compare the brightness variance of the first image with a second preset brightness variance threshold, compare the preset exposure gain of the photographing apparatus with a first preset exposure gain threshold, compare the preset exposure gain of the photographing apparatus with a second preset exposure gain threshold, and comparing the brightness average value of the face area in the first image with a first preset face brightness average value threshold, and determining the target scene type of the shooting scene where the face is currently located based on the comparison result. The first preset exposure effect value threshold, the second preset exposure effect value threshold, the third preset exposure effect value threshold, the first preset brightness variance threshold, the second preset brightness variance threshold, the first preset exposure gain threshold, the second preset exposure gain threshold, and the first preset face brightness average value threshold may all be set according to actual needs, and are not limited herein, for example, the first preset exposure effect value threshold may be 216, the second preset exposure effect value threshold may be 432, the third preset exposure effect value threshold may be 720, the first preset brightness variance threshold may be 2304, the second preset brightness variance threshold may be 1024, the first preset exposure gain threshold may be 8 times, the second preset exposure gain threshold may be 16 times, and the first preset face brightness average value threshold may be 90.

As an embodiment of the present application, S1025 may specifically include S401 to S403 shown in fig. 3, which are detailed as follows:

in S401, if the exposure effect value is greater than or equal to a first preset exposure effect value threshold and the brightness variance is greater than or equal to a first preset brightness variance threshold, it is determined that the target scene type is a backlight scene.

In this embodiment, when the photographing device detects that the exposure effect value of the first image is greater than or equal to the first preset exposure effect value threshold and the brightness variance of the first image is greater than or equal to the first preset brightness variance threshold, it indicates that the subject is backlit, and at this time, the photographing device determines that the target scene type is a backlit scene.

In S402, if the exposure effect value is greater than or equal to a second preset exposure effect value threshold and the brightness variance is greater than or equal to a second preset brightness variance threshold, determining that the target scene type is the backlight scene; the second preset exposure effect value threshold is greater than the first preset exposure effect value threshold, and the second preset brightness variance threshold is less than the first preset brightness variance threshold.

In this embodiment, when the photographing device detects that the exposure effect value of the first image is greater than or equal to the second preset exposure effect value threshold and the luminance variance of the first image is greater than or equal to the second preset luminance variance threshold, it indicates that the subject is backlit, and at this time, the photographing device determines that the target scene type is a backlit scene.

In S403, if the exposure effect value is greater than or equal to a third preset exposure effect value threshold, determining that the target scene type is the backlight scene; and the third preset exposure effect value threshold is greater than the second preset exposure effect value threshold.

In this embodiment, when the photographing device detects that the exposure effect value of the first image is greater than or equal to the third preset exposure effect value threshold, it indicates that the subject is backlit, and at this time, the photographing device determines that the target scene type is a backlit scene.

As another embodiment of the present application, S1025 may further include the following steps:

and if the exposure effect value is smaller than a first preset exposure threshold value, the brightness variance is smaller than a first preset brightness variance threshold value, the preset exposure gain is smaller than or equal to a first preset exposure gain threshold value, and the brightness average value of the face area is smaller than or equal to a first preset face brightness average value threshold value, determining that the target scene type is a first preset non-backlight scene.

In this embodiment, when the photographing device detects that the exposure effect value of the first image is smaller than a first preset exposure effect value threshold, the brightness variance of the first image is smaller than a first preset brightness variance threshold, the preset exposure gain of the photographing device is smaller than or equal to the first preset exposure gain threshold, and the brightness average value of the face area in the first image is smaller than or equal to the first preset face brightness average value threshold, it indicates that the photographic object is not backlit and the brightness of the photographic object is darker, and at this time, the photographing device determines that the target scene type is the first preset non-backlit scene.

Or, if the exposure effect value is smaller than a second preset exposure threshold, the brightness variance is smaller than a second preset brightness variance threshold, the preset exposure gain is smaller than or equal to the first preset exposure gain threshold, and the brightness average value of the face region is smaller than or equal to the first preset face brightness average value threshold, determining that the target scene type is the first preset non-backlight scene.

In this embodiment, when the photographing device detects that the exposure effect value of the first image is smaller than the second preset exposure effect value threshold, the brightness variance of the first image is smaller than the second preset brightness variance threshold, the preset exposure gain of the photographing device is smaller than or equal to the first preset exposure gain threshold, and the brightness average value of the face area in the first image is smaller than or equal to the first preset face brightness average value threshold, it indicates that the photographic object is not backlit and the brightness of the photographic object is darker, and at this time, the photographing device determines that the target scene type is the first preset non-backlit scene.

In this embodiment, when the photographing device detects that the exposure effect value of the first image is smaller than the third preset exposure effect value threshold, the preset exposure gain of the photographing device is smaller than or equal to the first preset exposure gain threshold, and the brightness average value of the face area in the first image is smaller than or equal to the first preset face brightness average value threshold, it indicates that the photographic object is not backlit and the brightness of the photographic object is dark, and at this time, the photographing device determines that the target scene type is the first preset non-backlit scene.

and if the exposure effect value is smaller than a first preset exposure threshold, the brightness variance is smaller than a first preset brightness variance threshold, the preset gain value is smaller than or equal to the first preset gain threshold, and the brightness average value of the face area is larger than the first preset face brightness average value threshold, determining that the target scene type is a common illumination scene.

In this embodiment, when the photographing device detects that the exposure effect value of the first image is smaller than the first preset exposure effect value threshold, the brightness variance of the first image is smaller than the first preset brightness variance threshold, the preset exposure gain of the photographing device is smaller than or equal to the first preset exposure gain threshold, and the brightness average value of the face area in the first image is greater than the first preset face brightness average value threshold, it indicates that the photographic object is not backlit and the brightness of the photographic object is not too dark, and at this time, the photographing device determines that the target scene type is a normal illumination scene.

Or, if the exposure effect value is smaller than a second preset exposure threshold, the brightness variance is smaller than a second preset brightness variance threshold, the preset gain value is smaller than or equal to the first preset gain threshold, and the brightness average value of the face area is greater than the first preset face brightness average value threshold, determining that the target scene type is the common illumination scene.

In this embodiment, when the photographing device detects that the exposure effect value of the first image is smaller than the second preset exposure effect value threshold, the brightness variance of the first image is smaller than the second preset brightness variance threshold, the preset exposure gain of the photographing device is smaller than or equal to the first preset exposure gain threshold, and the brightness average value of the face area in the first image is greater than the first preset face brightness average value threshold, it indicates that the photographic object is not backlit and the brightness of the photographic object is not too dark, and at this time, the photographing device determines that the target scene type is a normal illumination scene.

Or, if the exposure effect value is smaller than a third preset exposure threshold, the preset gain value is smaller than or equal to the first preset gain threshold, and the brightness average value of the face area is greater than the first preset face brightness average value threshold, determining that the target scene type is the common illumination scene.

In this embodiment, when the photographing device detects that the exposure effect value of the first image is smaller than the third preset exposure effect value threshold, the preset exposure gain of the photographing device is smaller than or equal to the first preset exposure gain threshold, and the brightness average value of the face area in the first image is greater than the first preset face brightness average value threshold, it indicates that the photographic object is not backlit and the brightness of the photographic object is not dark, and at this time, the photographing device determines that the target scene type is a normal illumination scene.

and if the exposure effect value is smaller than a first preset exposure threshold value, the brightness variance is smaller than a first preset brightness variance threshold value, the brightness average value of the face area is larger than a first preset face brightness average value threshold value, and the preset exposure gain is larger than a second preset exposure gain threshold value, determining that the target scene type is a low-light scene.

In this embodiment, when the shooting device detects that the exposure effect value of the first image is smaller than the first preset exposure effect value threshold, the brightness variance of the first image is smaller than the first preset brightness variance threshold, the brightness average value of the face area in the first image is larger than the first preset face brightness average value threshold, and the preset exposure gain of the shooting device is larger than the first preset exposure gain threshold, it indicates that the shooting object is not backlit, the brightness of the shooting object is not dark, and the illumination intensity of natural light of a shooting scene is weak, and at this time, the shooting device determines that the target scene type is a common illumination scene.

Or, if the exposure effect value is smaller than a second preset exposure threshold, the brightness variance is smaller than a second preset brightness variance threshold, the brightness average value of the face area is larger than the first preset face brightness average value threshold, and the preset exposure gain is larger than the second preset exposure gain threshold, determining that the target scene type is the low-light scene.

In this embodiment, when the shooting device detects that the exposure effect value of the first image is smaller than the second preset exposure effect value threshold, the brightness variance of the first image is smaller than the second preset brightness variance threshold, the brightness average value of the face area in the first image is larger than the first preset face brightness average value threshold, and the preset exposure gain of the shooting device is larger than the second preset exposure gain threshold, it indicates that the shooting object is not backlit, the brightness of the shooting object is not dark, and the illumination intensity of natural light of a shooting scene is weak, and at this time, the shooting device determines that the target scene type is a common illumination scene.

Or, if the exposure effect value is smaller than a third preset exposure threshold, the brightness average value of the face region is larger than the first preset face brightness average value threshold, and the preset exposure gain is larger than the second preset exposure gain threshold, determining that the target scene type is the low-light scene.

In this embodiment, when the shooting device detects that the exposure effect value of the first image is smaller than the third preset exposure effect value threshold, the brightness average value of the face area in the first image is larger than the first preset face brightness average value threshold, and the preset exposure gain of the shooting device is larger than the second preset exposure gain threshold, it indicates that the shooting object is not backlit, the brightness of the shooting object is not dark, and the illumination intensity of natural light of a shooting scene is weak, and at this time, the shooting device determines that the type of the target scene is a common illumination scene.

The embodiment determines the target scene type of the shooting scene where the face is currently located according to the exposure effect value of the first image, the brightness variance of the first image, the preset exposure gain of the shooting device and the brightness average value of the face area in the first image, and can improve the accuracy of scene type determination.

It should be noted that, in the embodiment of the present application, different scene types may correspond to different shooting modes, and different shooting modes may correspond to different operating states of the infrared lamp, so after the shooting device determines the target scene type, it is further required to determine a target shooting mode corresponding to the target scene type according to a preset corresponding relationship between the scene type and the shooting mode, and determine a target operating state of the infrared lamp corresponding to the target shooting mode according to a preset corresponding relationship between the shooting mode and the operating state of the infrared lamp.

Specifically, when detecting that the target scene type is a backlight scene, the shooting device executes S103; when detecting that the target scene type is a first preset non-backlight scene, the shooting device executes S201 shown in fig. 4; the photographing device performs S301 to S302 shown in fig. 5 when detecting that the type of the target scene is a low light scene or a normal lighting scene.

In S103, if the target scene type is a backlight scene, determining that a target shooting mode of the shooting device is a backlight shooting mode, and determining that a target operating state of the infrared lamp is an on state.

In the embodiment of the application, because the preset shooting mode corresponding to the backlight scene is the backlight shooting mode, when the shooting device detects that the type of the target scene is the backlight scene, the target shooting mode of the shooting device can be determined to be the backlight shooting mode; since the working state of the infrared lamp corresponding to the preset backlight shooting mode is the on state, when the shooting device determines that the target shooting mode is set to the backlight shooting mode, the target working state of the infrared lamp can be determined to be the on state.

In S104, the shooting mode is adjusted to be the backlight shooting mode, the current working state of the infrared lamp is adjusted to be the starting state, and then shooting is carried out, so that a target face image is obtained.

In the embodiment of the application, after determining that the target shooting mode is the backlight shooting mode and determining that the target working state of the infrared lamp is the on state, the shooting device adjusts the current shooting mode to be the backlight shooting mode and adjusts the current working state of the infrared lamp to be the on state, and then shooting is carried out, so that the target face image is obtained. The current working state refers to the working state of the infrared lamp when the shooting device shoots.

It should be noted that, in the embodiment of the present application, specifically, after the photographing device adjusts the target photographing mode to the backlight photographing mode and adjusts the target operating state of the infrared lamp to the on state, the photographing device collects images in the target photographing mode and the target operating state of the infrared lamp, and at this time, the collected image is a target face image, that is, an image with an improved face brightness.

In the above, the face image acquisition method provided by the embodiment of the application acquires the brightness information of the first image in the shooting mode; determining the type of a target scene of a shooting scene where the face is located at present according to the brightness information; if the type of the target scene is a backlight scene, determining that a target shooting mode of the shooting device is a backlight shooting mode, and determining that a target working state of an infrared lamp arranged on the shooting device is an opening state; and adjusting the shooting mode to be a backlight shooting mode and adjusting the current working state of the infrared lamp to be an opening state, and then shooting to obtain a target face image. Because when the shooting object is irradiated by the infrared lamp, the brightness of the shooting object can be improved, and meanwhile, natural light in the shooting scene cannot be influenced, so that when the human face to be shot is determined to be in the backlight scene, the brightness of the human face is improved by opening the infrared lamp on the shooting device while the backlight shooting mode corresponding to the backlight scene is adopted, the brightness of the human face is improved, the background information of the image cannot be lost while the brightness of the human face part in the target human face image is improved, and the overall quality of the target human face image is improved.

Referring to fig. 4, fig. 4 is a flowchart illustrating an implementation of a method for acquiring a face image according to another embodiment of the present application. With respect to the embodiment corresponding to fig. 1, the method for acquiring a face image provided in this embodiment may further include, after S102 and before S104, S201 shown in fig. 4, which is detailed as follows:

in S201, if the target scene type is a first preset non-backlight scene, determining that the target shooting mode is the backlight shooting mode, and determining that the target operating state of the infrared lamp is an on state.

In this embodiment, since the preset shooting mode corresponding to the first preset non-backlight scene is the backlight shooting mode, after the shooting device detects that the type of the target scene is the first preset non-backlight scene, it is determined that the target shooting mode of the shooting device is the backlight shooting mode, and since the working state of the infrared lamp corresponding to the preset backlight shooting mode is the on state, when the shooting device determines that the target shooting mode is set to the backlight shooting mode, it may be determined that the target working state of the infrared lamp is the on state.

In the above, it can be seen that according to the face image acquisition method provided by the embodiment of the application, when the type of the target scene is the first preset non-backlight scene, that is, the face to be photographed is not backlight and the face is dark, the target photographing mode of the photographing device is adjusted to the backlight photographing mode, and the current working state of the infrared lamp is adjusted to the on state, and as the infrared lamp is turned on, the brightness of the face in the image can be improved, and meanwhile, the background information of the image cannot be lost, so that the overall quality of the target face image can be improved.

Referring to fig. 5, fig. 5 is a flowchart illustrating an implementation of a method for acquiring a face image according to another embodiment of the present application. With respect to the embodiment corresponding to fig. 1, the face image acquisition method provided by this embodiment can be further implemented by S301 to S302 shown in fig. 3 after S102, which is detailed as follows:

in S301, if the type of the target scene is a low-light scene or a normal-illumination scene, it is determined that the target shooting mode is a normal shooting mode, and it is determined that the target operating state of the infrared lamp is an off state.

In this embodiment, since the preset shooting mode corresponding to the low-light scene is the normal shooting mode, and the shooting mode corresponding to the normal lighting scene is also the normal shooting mode, after the shooting device detects that the type of the target scene is the low-light scene or the normal lighting scene, it is determined that the target shooting mode of the shooting device is the normal shooting mode, and since the working state of the infrared lamp corresponding to the preset normal shooting mode is the off state, when it is determined that the target shooting mode is set to the normal shooting mode, the shooting device determines that the target working state of the infrared lamp is the off state.

In practical application, because the light intensity on daytime is enough to make the shooting device obtain clear image including the people's face under ordinary shooting mode, need not carry out extra light filling through the infrared lamp, and the light intensity at night is not enough to make the shooting device obtain clear image including the people's face under ordinary shooting mode, needs the infrared lamp to carry out extra light filling in order to obtain the image including clear people's face under ordinary shooting mode. Therefore, in an embodiment of the present application, when the ordinary shooting mode is turned on in the first state, the target operating state of the corresponding infrared lamp may be set to be the off state in advance; when the common shooting mode is started in the second state, the target working state of the corresponding infrared lamp is in a starting state. The first state is used for indicating that the shooting device is in a daytime state, and the second state is used for indicating that the shooting device is in a night state. Note that the image in the normal shooting mode may be a different image from the first image.

It should be noted that, in this embodiment, whether the photographing device is in the daytime state or the nighttime state may be determined according to a magnitude relationship between the preset exposure gain of the photographing device and the third preset exposure gain threshold. Specifically, if the preset exposure gain of the shooting device is smaller than the third preset exposure gain threshold, determining that the shooting device is in a daytime state; and if the preset exposure gain of the shooting device is greater than or equal to the third preset exposure gain threshold value, determining that the shooting device is in a night state. The third preset exposure gain threshold may be set according to actual needs, and is not limited herein.

Based on this, as an embodiment of the present application, after determining that the target shooting mode is the normal shooting mode, the shooting device may further determine the target operating state of the infrared lamp according to the state of the shooting device at the current time. The current time refers to the time when the shooting device determines the target shooting mode. Specifically, if the state of the shooting device at the current moment is a first state, determining that the target working state of the infrared lamp is a closed state; and if the state of the shooting device at the current moment is the second state, determining that the target working state of the infrared lamp is the starting state.

In this embodiment, the photographing device executes S302 when determining that the target operating state of the infrared lamp is the off state; when the shooting device determines that the target working state of the infrared lamp is the starting state, the current shooting mode of the shooting device is adjusted to be the common shooting mode, the current working state of the infrared lamp is adjusted to be the starting state, and then shooting is carried out, so that a target face image is obtained.

In S302, the shooting mode is adjusted to the normal shooting mode, and the current working state of the infrared lamp is adjusted to the off state, and then shooting is performed, so as to obtain the target face image.

In the embodiment of the application, after the shooting device determines that the target shooting mode is the common shooting mode and the target working state of the infrared lamp is the off state, the shooting device adjusts the shooting mode to be the common shooting mode and adjusts the current working state of the infrared lamp to be the off state, and then shooting is carried out, so that the target face image is obtained.

As an embodiment of the application, when the light intensity of the infrared lamp is too low, the infrared lamp is turned on, so that the aim of supplementing light to the image in the target shooting mode and further improving the brightness of the face in the image in the target shooting mode cannot be achieved; however, when the light intensity of the infrared lamp is too high, the infrared lamp is turned on to overexpose the image in the target shooting mode, so that a clear image cannot be obtained, and therefore, in another embodiment of the present application, after S103 and before S104, the face image capturing method may further include S1026 to S1027 shown in fig. 6, which are described in detail as follows:

in S1026, the target lamp light intensity of the infrared lamp is determined based on the average value of the brightness of the face region.

In this embodiment, after the photographing device determines that the target working state of the infrared lamp is the on state, the target lamp light intensity of the infrared lamp may be determined based on the average brightness value of the face region.

As a specific embodiment of the present application, the photographing device may determine the target lamp light intensity of the infrared lamp based on the following formula:

wherein power represents the target light intensity of the infrared lamp, and face _ value represents the average value of the brightness of the face region in the first image.

In S1027, the current lamp light intensity of the infrared lamp is adjusted to the target lamp light intensity.

In this embodiment, after determining the target light intensity of the infrared lamp, the photographing device adjusts the current light intensity of the infrared lamp to the target light intensity.

As can be seen from the above, in the face image acquisition method provided by this embodiment, the target light intensity of the infrared lamp is determined based on the average brightness value of the face region; the current lamplight intensity of the infrared lamp is adjusted to the target lamplight intensity, so that the image is not overexposed while the brightness of the image in the target shooting mode is improved, and the quality of the image is improved.

As an embodiment of the present application, the photographing device may include, in addition to the lens and the light sensing element, a first filter, a second filter, and a switching member for switching the first filter and the second filter, which are disposed between the lens and the light sensing element. The first optical filter is used for passing visible light and filtering infrared light. The second optical filter is used for passing infrared light and visible light with preset wavelength. The preset wavelength can be set according to actual needs, and is not limited herein.

In practical applications, the switching component may be, by way of example and not limitation, an infra-filter CUT (IR-CUT); the first filter may be a blue filter; the second filter can be a double-pass filter, and the double-pass filter refers to a filter which can pass infrared light and visible light.

In this embodiment, since the target operating state of the infrared lamp corresponding to the preset normal shooting mode is the off state, that is, in the normal shooting mode, the light entering the lens only includes visible light and does not include infrared light, the optical filter corresponding to the normal shooting mode can be preset as the first optical filter. The preset target working state of the infrared lamp corresponding to the backlight shooting mode is the on state, that is, the light entering the lens in the backlight shooting mode contains visible light and infrared light, so that the optical filter corresponding to the backlight shooting mode can be preset as the second optical filter. The photographing device may store a preset correspondence between the photographing mode and the optical filter in association.

Based on this, as an embodiment of the present application, after the photographing device determines that the target photographing mode is the backlight photographing mode and determines that the target operating state of the infrared lamp is the on state, the switching component may be further controlled to switch the first optical filter and the second optical filter, so that the second optical filter is disposed between the lens and the photosensitive element, and the light emitted from the lens to the photosensitive element is filtered through the second optical filter, so that the infrared light and the visible light with the preset wavelength emitted into the lens can reach the photosensitive element and be sensed by the photosensitive element.

As another embodiment of the present application, after determining that the target shooting mode is the normal shooting mode and determining that the target operating state of the infrared lamp is the off state, the shooting device may further control the switching component to switch the first optical filter and the second optical filter, so that the first optical filter is disposed between the lens and the photosensitive element to filter the infrared light emitted from the lens to the photosensitive element through the first optical filter, so that the visible light emitted into the lens can reach the photosensitive element and be sensed by the photosensitive element.

In this embodiment, the photographing device switches the first optical filter and the second optical filter by controlling the switching component, so that in the backlight photographing mode, infrared light can be sensed by a photosensitive element in the photographing device, thereby achieving the purpose of supplementing light to an image in the backlight photographing mode. Note that the image in the backlight shooting mode and the first image may be different images.

As another embodiment of the present invention, after the light is filtered by the optical filter, different color ratios in the second image currently displayed on the shooting interface of the shooting device are unbalanced, and the overall image quality of the second image is affected, so that when the light is filtered by the optical filter, the second image can be further processed based on the preset image processing parameters. Wherein the current time refers to the time when the photographing apparatus determines the target photographing mode.

Because the light rays filtered by different optical filters are different, the values of the preset image processing parameters corresponding to different optical filters are different. Specifically, the value of the preset image processing parameter corresponding to the first optical filter may be preset as a first preset parameter value, and the value of the preset image processing parameter corresponding to the second optical filter may be preset as a second preset parameter value. The preset image processing parameters may be set according to actual needs, and are not limited herein, and for example, the preset image processing parameters may include a white balance parameter, a color matrix parameter, a sharpening parameter, and a noise reduction parameter. The photographing device may store a preset correspondence between the optical filter and a value of a preset image processing parameter in association.

Based on this, the photographing device may further include the following steps after controlling the switching means to switch the first filter and the second filter and placing the target filter corresponding to the target photographing mode between the lens and the photosensitive element:

determining a value of a preset image processing parameter corresponding to the target optical filter based on a preset corresponding relationship between the optical filter and the value of the preset image processing parameter;

and performing image processing on the second image based on the value of the preset image processing parameter corresponding to the target optical filter.

In this embodiment, since the preset image processing parameters include a white balance parameter, a color matrix parameter, a sharpening parameter, and a noise reduction parameter, after determining a white balance value, a color matrix value, a sharpening value, and a noise reduction value corresponding to the target optical filter, the photographing device may respectively adjust the white balance value and the color matrix value of the image in the target photographing mode based on the white balance value and the color matrix value corresponding to the target optical filter, and may balance color ratios in the second image by adjusting the white balance value and the color matrix value of the second image; meanwhile, the shooting device also carries out sharpening and noise reduction processing on the second image based on the sharpening value and the noise reduction value, edges and details of the second image can be optimized through sharpening and noise reduction processing, and the overall quality of the second image is improved.

As another embodiment of the present application, after determining that the target photographing mode is the backlight photographing mode, the photographing device may further perform gamma conversion on the second image based on an exposure effect value of the first image.

The gamma conversion of the second image means that the image is corrected, that is, the luminance of the portion of the image with a darker luminance is improved and the luminance of the portion of the image with a brighter luminance is reduced by correcting the portion of the image with an excessively high luminance or the portion of the image with an excessively low luminance.

In this embodiment, the intensity values of the gamma transformation corresponding to different shooting scenes may be different.

Specifically, when the target scene type is a backlight scene, the photographing device may determine the gamma-transformed intensity value according to the exposure effect value of the first image. More specifically, the camera may determine the gamma-transformed intensity values based on the following formula:

where dark _ str denotes an intensity value of the gamma transformation, exp _ value denotes an exposure effect value of the first image, D1 denotes a maximum value of the intensity value of the gamma transformation in the backlight scene, and D2 denotes a minimum value of the intensity value of the gamma transformation in the backlight scene. The maximum value and the minimum value of the intensity value of the gamma conversion can be set according to actual needs, and are not limited herein, for example, in a backlight scene, the maximum value of the intensity value of the gamma conversion can be 128, and the minimum value of the intensity value of the gamma conversion can be 64.

When the target scene type is the first preset non-backlight scene, the shooting device may determine the intensity value of the gamma change according to the average value of the brightness of the face region. Specifically, the camera may determine the gamma-transformed intensity value according to the following formula:

where dark _ str represents the intensity value of the gamma transformation, face _ value represents the average value of the brightness of the face region in the first image, D3 represents the maximum value of the intensity value of the gamma transformation in the first preset non-backlit scene, and D4 represents the minimum value of the intensity value of the gamma transformation in the first preset non-backlit scene. The maximum value and the minimum value of the intensity value of the gamma conversion can be set according to actual needs, and are not limited herein, for example, in the first preset non-backlight scene, the maximum value of the intensity value of the gamma conversion can be 96, and the minimum value of the intensity value of the gamma conversion can be 48.

As can be seen from the above, the method for acquiring a face image according to the embodiment can improve the brightness of the face detail part of the second image by performing gamma conversion on the second image, and further improve the quality of the second image.

After the second image in the target shooting mode is subjected to image processing by the shooting device, the second image subjected to image processing can be collected, and the image is a target face image.

It should be understood that, the sequence numbers of the steps in the foregoing embodiments do not imply an execution sequence, and the execution sequence of each process should be determined by its function and inherent logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

Fig. 7 shows a structural block diagram of a shooting device provided in the embodiment of the present application, and for convenience of description, only the parts related to the embodiment of the present application are shown. The shooting device provided by the embodiment is provided with an infrared lamp used for emitting infrared light to a shooting object. In practical applications, the photographing device may include, but is not limited to, various electronic devices having a photographing function, such as a video camera, a mobile phone, and a monitoring device. In the embodiment of the application, the shooting object can be any face entering the shooting range of the shooting device. Referring to fig. 7, the photographing apparatus 700 includes: an acquisition unit 71, a first determination unit 72, a second determination unit 73, and a first adjustment unit 74. Wherein:

the acquiring unit 71 is configured to acquire, in a shooting mode, brightness information of a first image currently displayed on a shooting interface; the first image comprises a human face.

The first determining unit 72 is configured to determine a target scene type of a shooting scene where the face is currently located according to the brightness information.

The second determining unit 73 is configured to determine that the target shooting mode of the shooting device is the backlight shooting mode and determine that the target working state of the infrared lamp is the on state if the target scene type is the backlight scene.

The first adjusting unit 74 is configured to adjust the shooting mode to the backlight shooting mode and adjust the current working state of the infrared lamp to the on state, and then shoot the image to obtain a target face image.

As an embodiment of the application, the luminance information is used to describe a luminance value of each pixel included in the first image, and accordingly, the first determining unit 72 may specifically include: the device comprises an image average value determining unit, a variance determining unit, an exposure effect value determining unit, a face average value determining unit and a scene determining unit. Wherein:

the image average value determining unit is used for determining the brightness average value of the first image according to the brightness values of all the pixels contained in the first image.

The variance determining unit is used for determining the brightness variance of the first image according to the brightness average value.

The exposure effect value determining unit is used for determining the exposure effect value of the first image according to the brightness average value, the preset shutter speed of the shooting device and the preset exposure gain of the shooting device.

The face average value determining unit is used for determining the brightness average value of the face area according to the brightness values of the pixels contained in the face area in the first image.

The scene determining unit is used for determining the target scene type according to the brightness variance, the preset exposure gain, the exposure effect value and the brightness average value of the face area.

As an embodiment of the present application, the scene determining unit specifically includes: a backlight scene determination unit.

The backlight scene determining unit is used for determining that the target scene type is a backlight scene if the exposure effect value is greater than or equal to a first preset exposure effect value threshold and the brightness variance is greater than or equal to a first preset brightness variance threshold;

or determining that the target scene type is the backlight scene if the exposure effect value is greater than or equal to a second preset exposure effect value threshold and the brightness variance is greater than or equal to a second preset brightness variance threshold; the second preset exposure effect value threshold is greater than the first preset exposure effect value threshold, and the second preset brightness variance threshold is less than the first preset brightness variance threshold.

Or determining that the target scene type is the backlight scene if the exposure effect value is greater than or equal to a third preset exposure effect value threshold; and the third preset exposure effect value threshold is greater than the second preset exposure effect value threshold.

As an embodiment of the present application, the second determining unit 73 is further configured to:

if the target scene type is a first preset non-backlight scene, determining that the target shooting mode is a backlight shooting mode, and determining that the target working state of the infrared lamp is an opening state; the first preset non-backlight scene is used for describing a shooting scene in which the human face is not backlight and the brightness of the human face is dark.

and if the type of the target scene is a weak light scene or a common illumination scene, determining that the target shooting mode is a common shooting mode, and determining that the target working state of the infrared lamp is a closed state.

The first adjusting unit 74 is further configured to:

As an embodiment of the present application, the photographing apparatus 700 may further include: an infrared lamp intensity determination unit and a second adjustment unit. Wherein:

the infrared lamp intensity determination unit is used for determining the target lamp intensity of the infrared lamp based on the average brightness value of the human face area.

The second adjusting unit is used for adjusting the current lamplight intensity of the infrared lamp to the target lamplight intensity.

As an embodiment of the present application, the scene determining unit may further include: a first preset non-backlit scene determining unit.

The first preset non-backlight scene determining unit is configured to determine that the target scene type is a first preset non-backlight scene if the exposure effect value is smaller than a first preset exposure threshold, the brightness variance is smaller than a first preset brightness variance threshold, the preset exposure gain is smaller than or equal to a first preset exposure gain threshold, and the brightness average of the face region is smaller than or equal to a first preset face brightness average threshold.

Or determining that the target scene type is the first preset non-backlight scene if the exposure effect value is smaller than a second preset exposure threshold, the brightness variance is smaller than a second preset brightness variance threshold, the preset exposure gain is smaller than or equal to the first preset exposure gain threshold, and the brightness average value of the face region is smaller than or equal to the first preset face brightness average value threshold.

Or the target scene type is determined to be the first preset non-backlight scene if the exposure effect value is smaller than a third preset exposure threshold, the preset exposure gain is smaller than or equal to the first preset exposure gain threshold, and the brightness average value of the face region is smaller than or equal to the first preset face brightness average value threshold.

As an embodiment of the present application, the scene determining unit may further include: a general lighting scene determination unit.

The common illumination scene unit is used for determining that the target scene type is a common illumination scene if the exposure effect value is smaller than a first preset exposure threshold, the brightness variance is smaller than a first preset brightness variance threshold, the preset gain value is smaller than or equal to a first preset gain threshold, and the brightness average value of the face area is larger than a first preset face brightness average value threshold.

Or the target scene type is determined to be the common illumination scene if the exposure effect value is smaller than a second preset exposure threshold, the brightness variance is smaller than a second preset brightness variance threshold, the preset gain value is smaller than or equal to the first preset gain threshold, and the brightness average value of the face region is larger than the first preset face brightness average value threshold.

Or the target scene type is determined to be the common illumination scene if the exposure effect value is smaller than a third preset exposure threshold, the preset gain value is smaller than or equal to the first preset gain threshold, and the brightness average value of the face region is larger than the first preset face brightness average value threshold.

As an embodiment of the present application, the scene determining unit may further include: a low light scene determination unit.

The weak light scene determining unit is used for determining that the target scene type is a weak light scene if the exposure effect value is smaller than a first preset exposure threshold, the brightness variance is smaller than a first preset brightness variance threshold, the brightness average value of the face area is larger than a first preset face brightness average value threshold, and the preset exposure gain is larger than a second preset exposure gain threshold.

Or the target scene type is determined to be the low-light scene if the exposure effect value is smaller than a second preset exposure threshold, the brightness variance is smaller than a second preset brightness variance threshold, the brightness average value of the face area is larger than the first preset face brightness average value threshold, and the preset exposure gain is larger than the second preset exposure gain threshold.

Or the exposure effect value is smaller than a third preset exposure threshold, the brightness average value of the face area is larger than the first preset face brightness average value threshold, and the preset exposure gain is larger than the second preset exposure gain threshold, and then the target scene type is determined to be the low-light scene.

As can be seen from the above, in the shooting mode, the shooting device provided by the application obtains the brightness information of the first image; determining the type of a target scene of a shooting scene where the face is located at present according to the brightness information; if the type of the target scene is a backlight scene, determining that a target shooting mode of the shooting device is a backlight shooting mode, and determining that a target working state of an infrared lamp arranged on the shooting device is an opening state; and adjusting the shooting mode to be a backlight shooting mode and adjusting the current working state of the infrared lamp to be an opening state, and then shooting to obtain a target face image. Because when the shooting object is irradiated by the infrared lamp, the brightness of the shooting object can be improved, and meanwhile, natural light in the shooting scene cannot be influenced, so that when the human face to be shot is determined to be in the backlight scene, the brightness of the human face is improved by opening the infrared lamp on the shooting device while the backlight shooting mode corresponding to the backlight scene is adopted, the brightness of the human face is improved, the background information of the image cannot be lost while the brightness of the human face part in the target human face image is improved, and the overall quality of the target human face image is improved.

It should be noted that, for the information interaction, the execution process, and other contents between the above units, the specific functions and the technical effects of the embodiments of the method of the present application are based on the same concept, and specific reference may be made to the above embodiments of the method, and details are not described here.

It will be apparent to those skilled in the art that, for convenience and brevity of description, only the above-mentioned division of the functional units and modules is illustrated, and in practical applications, the above-mentioned function distribution may be performed by different functional units and modules according to needs, that is, the internal structure of the apparatus is divided into different functional units or modules to perform all or part of the above-mentioned functions. Each functional unit and module in the embodiments may be integrated in one processing unit, or each unit may exist alone physically, or two or more units are integrated in one unit, and the integrated unit may be implemented in a form of hardware, or in a form of software functional unit. In addition, specific names of the functional units and modules are only for convenience of distinguishing from each other, and are not used for limiting the protection scope of the present application. The specific working processes of the units and modules in the system may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

Fig. 8 is a schematic structural diagram of a shooting device according to an embodiment of the present application. As shown in fig. 8, the photographing device 8 of this embodiment includes: at least one processor 80 (only one is shown in fig. 8), a memory 81, and a computer program 82 stored in the memory 81 and operable on the at least one processor 80, wherein the processor 80 executes the computer program 82 to implement the steps in any of the above-mentioned embodiments of the face image acquisition method.

The shooting device 8 may be a desktop computer, a notebook, a palm computer, a cloud shooting device, or other computing devices. The camera may include, but is not limited to, a processor 80, a memory 81. Those skilled in the art will appreciate that fig. 8 is merely an example of the camera 8, and does not constitute a limitation on the camera 8, and may include more or less components than those shown, or combine some components, or different components, such as input and output devices, network access devices, etc.

The Processor 80 may be a Central Processing Unit (CPU), and the Processor 80 may be other general purpose Processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), an off-the-shelf Programmable Gate Array (FPGA) or other Programmable logic device, discrete Gate or transistor logic, discrete hardware components, etc. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

The memory 81 may in some embodiments be an internal storage unit of the camera 8, such as a hard disk or a memory of the camera 8. In other embodiments, the memory 81 may also be an external storage device of the camera 8, such as a plug-in hard disk, a Smart Media Card (SMC), a Secure Digital (SD) Card, a Flash memory Card (Flash Card), or the like, provided on the camera 8. Further, the memory 81 may also include both an internal storage unit and an external storage device of the photographing apparatus 8. The memory 81 is used for storing an operating system, an application program, a BootLoader (BootLoader), data, and other programs, such as program codes of the computer program. The memory 81 may also be used to temporarily store data that has been output or is to be output.

An embodiment of the present application further provides a computer-readable storage medium, where a computer program is stored, and when the computer program is executed by a processor, the steps in any one of the above embodiments of the face image acquisition method can be implemented.

The embodiment of the application provides a computer program product, and when the computer program product runs on a mobile terminal, the steps in any one of the above embodiments of the face image acquisition method can be realized when the mobile terminal is executed.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, all or part of the processes in the methods of the embodiments described above can be implemented by a computer program, which can be stored in a computer-readable storage medium and can implement the steps of the embodiments of the methods described above when the computer program is executed by a processor. Wherein the computer program comprises computer program code, which may be in the form of source code, object code, an executable file or some intermediate form, etc. The computer readable medium may include at least: any entity or device capable of carrying computer program code to a photographing apparatus/terminal apparatus, a recording medium, computer Memory, Read-Only Memory (ROM), random-access Memory (RAM), an electrical carrier signal, a telecommunications signal, and a software distribution medium. Such as a usb-disk, a removable hard disk, a magnetic or optical disk, etc. In certain jurisdictions, computer-readable media may not be an electrical carrier signal or a telecommunications signal in accordance with legislative and patent practice.

In the above embodiments, the descriptions of the respective embodiments have respective emphasis, and reference may be made to the related descriptions of other embodiments for parts that are not described or illustrated in a certain embodiment.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

In the embodiments provided in the present application, it should be understood that the disclosed face image acquisition method and shooting device may be implemented in other manners. For example, the above-described embodiments of the camera are merely illustrative, and for example, the division of the modules or units is only one logical division, and there may be other divisions when actually implemented, for example, a plurality of units or components may be combined or may be integrated into another system, or some features may be omitted or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

The above-mentioned embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present application and are intended to be included within the scope of the present application.

Claims

1. A human face image acquisition method is applied to a shooting device and is characterized in that an infrared lamp used for emitting infrared light to a shooting object is arranged on the shooting device, and the human face image acquisition method comprises the following steps:

2. The method for acquiring the face image according to claim 1, wherein the brightness information is used for describing a brightness value of each pixel contained in the first image;

correspondingly, the determining the target scene type of the shooting scene where the face is currently located according to the brightness information includes:

3. The method for acquiring a human face image according to claim 2, wherein the determining the target scene type according to the brightness variance, the preset exposure gain, the exposure effect value and the brightness average value of the human face region comprises:

or, if the exposure effect value is greater than or equal to a second preset exposure effect value threshold and the brightness variance is greater than or equal to a second preset brightness variance threshold, determining that the target scene type is the backlight scene; the second preset exposure effect value threshold is greater than the first preset exposure effect value threshold, and the second preset brightness variance threshold is less than the first preset brightness variance threshold;

4. The method for acquiring a human face image according to claim 2, wherein the determining the target scene type according to the brightness variance, the preset exposure gain, the exposure effect value and the brightness average value of the human face region comprises:

5. The method according to any one of claims 1 to 4, wherein after determining the target scene type of the shooting scene where the human face is currently located according to the brightness information, before performing shooting after adjusting the shooting mode to the backlight shooting mode and adjusting the current operating state of the infrared lamp to the on state, the method further comprises:

6. The method for acquiring a human face image according to any one of claims 1 to 4, wherein after the determining the target scene type of the shooting scene where the human face is currently located according to the brightness information, the method further comprises:

7. The method for acquiring a human face image according to claim 2, wherein after determining that the target shooting mode of the shooting device is a backlight shooting mode and determining that the target working state of the infrared lamp is an on state, before shooting, the method further comprises:

8. A photographing apparatus provided with an infrared lamp for emitting infrared light to a subject, the photographing apparatus comprising:

9. A camera comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that the processor implements the method according to any of claims 1 to 7 when executing the computer program.

10. A computer-readable storage medium, in which a computer program is stored which, when being executed by a processor, carries out the method according to any one of claims 1 to 7.